Automatic batch weighing system

ABSTRACT

An automatic batch weighing system for compounding a series of batches containing predetermined measured quantities of various constituents. The constituents for each batch are successively fed into a batch receiving hopper. The compounded constituents are thereafter mixed in a mixing hopper and delivered to a selected utilizing means. The feeding of each constituent is adjusted by estimating the weight of an unpredictable dribble and by compensating for any deviation in the most recent batch compounded for the selected utilizing means, to average out errors in the series of batches.

United States Patent 1 1 Inventor riemJr. 3,156,312 11/1964 Heltzel etal177/70 N fl h 3,167,139 1/1965 Schellentrager... 177/70 [21] Appl. N 85,951 3,203,591 8/1965 Daulton et a1. 177/70X [22] il p ,1 3,362,490l/l968 Maxwell 177/70 [45] Patented July 27, 1 D 3,477,529 11/1969 Burnet a1. 177/70X [73] Assign Owens'commg Corporauon PrimaryExaminer-Richard B. Wilkinson Assistant Examiner-George H. Miller, Jr.[54] AUTOMATIC BATCH wElGHING SYSTEM Attorneys-Staelin & Overman andOliver E. Todd, Jr.

10 Claims, 2 Drawing Figs.

[52] U.S.Cl 177/1,

177/70 ABSTRACT: An automatic batch weighing system for com- IIEL .Q .I-

ounding a eries of batches containing predetermined mea- 0' 70, -edquantities of various constituents The constituents for 2! 1 each batchare successively fed into a batch receiving hopper. 56 R I CW Thecompounded constituents are thereafter mixed in a mixl e ing hopper anddelivered to a selected utilizing means. The UNITED STATES PATENTSfeeding of each constituent is adjusted by estimating the 2,587,5312/1952 Saxe 177/70 UX weight of an unpredictable dribble and bycompensating for 2,712,203 7/1955 Green 177/70 X any deviation in themost recent batch compounded for the 2,780,456 2/1957 Berwaens.....177/70 X selected utilizing means, to average out errors in the seriesof 3,106,974 10/1963 Wi11iams,Jr 177/70 batches.

I? 14' If i .52 1 Z 3 ,1 i 1 1 PRINTER l I 7 1 7 7 7 2157 SWITC11ING C1CU T5 I 1; 15 R 27 20 Z 23 H o r g R 7 7/ V 7 ANALOG J BATCH f5CONVERTER AUTOMATIC BATCH WEIGIIING SYSTEM BACKGROUND OF THE INVENTIONThis invention relates to a weighing system and more particularly to animproved method for sequentially compounding predetermined quantities ofa plurality of constituents to form a batch and wherein errors insuccessive batches are compensated for.

Typically, batch weighing systems operate on one of two generalprinciples. In one system, the various batch constituents areindividually weighed prior to compounding in a batch receiving hopper.Either a separate scale is used for each constituent or the constituentsare individually and sequentially weighed on a single scale andindividually dumped into the batch receiving hopper. The cost of havinga separate scale for each constituent may be prohibitively high and thefinal batch may be inaccurate due to variations between the scales. Ineither case, the final batch is also subjectto inaccuracies occurringfrom the apparatus usedfor feeding the various constituents to thescale.

In the second type of batch weighing system, the various batchconstituents are sequentially accumulated in a batch receiving hopperwhich is mounted either on a'fulcrumed weight beam or on a strain gaugefor determining the weight of the hopper and its contents. The systemmay be controlled in response to eitherthe total weight of the batchconstituents accumulated in the hopper or to the weight increment aseach constituent is sequentially fed into the hopper. If "the totalweight is used to control the system and if, for example, 40

pounds ofa first batch constituent and. pounds of a second batchconstituent are desired, then control points are set at 40 pounds forthe first constituent and at 40 plus 10 or 50 pounds for the secondconstituent. Thus,lthe feeding of the first constituent will be stoppedwhen the scalesenses a weight of 40 pounds and the feeding of the secondconstituent will be stopped when the scale senses a weight of 50 pounds.This type of control system is undesirable, however, because weighterrors are cumulative. If 42 pounds of the first constituent areactually fed into the hopper instead of the desired 40 pounds, due tovariations in-the feeding operation, then only 8 pounds of the secondconstituent will be fed, resulting in nearly a 24 percent error in theconstituent proportions. If on the other hand the system is controlledby using only the weight increment of each successive constituent,cumulative errors are eliminated.

Measurement errors usually occur in the prior art batch weighing systemsdue to variations in the constituent feeding equipment. If, for example,the batch constituents are fed into a batch receiving hopper byindividual feed screws for each constituent, errors may occur for eachconstituent due to the position of the feed screw when it is stopped,due to the wear of the feed screw, and due to particle size, packing andmoisture content of the constituent. Furthermore, the feed screws aretypically mounted some distance above the batch receiving hopper. When afeed screw is stopped, there will be some material falling from the feedscrew into the hopper which will cause measurement errors. Attemptstoeliminate measurement errors occurring in the above systems have metwith varying degrees of success.

SUMMARY OF THE INVENTION According to the instant invention, successivebatches composed of predetermined measured weights-of variousconstituents are compounded in a batch receiving hopper by sequentiallyaccumulating the constituents in the hopper. Each constituent isaccumulated first at a fast feed rate and, when less than apredetermined slow feed rate remains to be fed, at a slow feed rate.Prior to feeding each constituent into the hopper, a scale tare isdetermined by weighing the hopper and all constituent is fed into thebatch receiving hopper, the weight of the hopper andthe constituentstherein is compared to a high preset weight and a low preset weightwhich are determined by a batch controller. The high preset weightcomprises the scale tare plus the predetermined measured weight for theconstituent being fed less an estimated unpredictable dribble weight forthe constituent being fed and less error weight determined for theconstituent being fed. The low preset comprises the high preset less apredetermined slow feed weight.

When the total weight of the batch receiving hopper and the constituentstherein is less than the low preset weight, a selected constituent isfed into the batch receiving hopper at a fast rate. When the totalweight of the batch receiving hopper and the constituents thereinexceeds the low preset weight but is less than the high preset weight,the selected constituent is fed at a slow rate. Feeding is stopped whenthe total weight of the batch receiving hopper and the constituentstherein reaches the high preset weight. Although feeding is stopped, andunpredictable dribble quantity of the selected constituent will fallinto the hopper. The dribble quantity results from the final positionand condition of the feeding apparatus, the condition of the selectedconstituent and the quantity of the constituent falling from the feedingapparatus into the hopper at the time feeding is stopped. If the actualdribble weight deviates from the estimated dribble weight for theselected constituent, a new estimated unpredictable dribble weight isdetermined for the next batch and an error weight is determined tocompensate for the deviation. After all ofthe various batch constituentsare accumulated in the batch receiving hopper, they are delivered to amixing hopper and, after mixing, they are delivered to a selectedutilizing means.

The above method is particularly suitable for use in the glass industryfor successively compounding batches of glass constituents for variousglass furnaces wherein each furnace requires a different mixture of theconstituents. A separate storage hopper is usually positioned adjacentto each glass furnace for holding a number of batches compounded for thefurnace. Each batch of constituents which is sequentially fed into astorage hopper is compensated for measurement errors in the previousbatch delivered to the hopper. Since a glass furnace may hold as many as20 or more batches, the errors are averaged out and the resulting glasswill be extremely close to its desired formula. The various batchformulas for the various furnaces are stored in a batch controller whichselects the furnace for which the batch is compounded and controls thefeeding ofthe various batch constituents into the batch receivinghopper.

It is the primary object of this invention to provide an improved methodfor the separate compounding of a series ofindividual batches containingpredetermined measured weights of various constituents, each of whichbatches is to be delivered to a selected utilizing means.

Other objects and advantages will become apparent from the followingdetailed description, reference being made to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. I is a schematic block diagram ofa batch weighing system incorporating the instant invention; and

FIG. 2 is a schematic circuit diagram of the switching circuits forcontrolling the feeding operation for the various batch constituents.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to FIG. 1, a blockdiagram is shown of a weighing system incorporating the instantinvention. The various batch constituents are fed from storage hoppersor other suitable sources into a batch receiving hopper 11. A firstconstituent storage hopper 12 having a feed control means 13, a secondconstituent storage hopper 14 having a feed control means 15 and a thirdconstituent storage hopper l6.having a feed control means 17 are shown,although any number of storage hoppers may be connected for discharginginto the batch receiving hopper 11. The constituent feed control means13, and 17 may, for example, comprise a valve, a feed screw, or aconveyor.

The batch receiving hopper 11 is shown mounted on a pair of straingauges 18 which are serially connected to have an analogue outputvoltage proportional to the total weight of the batch receiving hopper11 and the constituents accumulated therein. The analogue output voltageof the strain gauge 18 is connected to the input of ananalogue-to-digital converter 19 which has a binary coded decimal(B.C.D.) output corresponding to the total weight of the batch receivinghopper l1 and the constituents accumulated therein. The B.C.D. output ofthe converter 19 is applied to one input of a conventional comparator20. The comparator 20 compares the digital output of the converter 19with a high preset output 21 and a low preset output 22 from a batchcontroller 23. The high preset output 21 and the low preset output 22are each in the form of a B.C.D., similar to the B.C.D. output of theconverter 19. An output 24 of the comparator 20, as well as an output 25from the batch controller 23 are applied to switching circuits 26 forcontrolling the constituent feed control means 13, 15 and 17. Signalsapplied on the output 25 of the batch controller 23 control theswitching'circuit 26 to select the constituent to be fed and to initiatethe feeding operation. Once the feeding of a constituent is initiated,the feeding will continue at a fast rate so long as the comparator 20senses that the total weight of the hopper 11 and the constituentsaccumulated therein, as taken at the output of the converter 19, is lessthan the low preset 22. As soon as the output of the converter 19reaches the low preset output 22, the comparator 20 applies a signal tothe switching circuits 26 through its output 24 to initiate feeding at aslow rate. The comparator 20 applies a second signal to the switchingcircuit 26 when the output of the converter 19 matches or exceeds thehigh preset output 21 of the batch controller 23. The second signalcauses the switching circuits 26 to stop the feeding operation.

When the feeding operation is stopped, the switching circuits 26 apply asignal through an output 27 to the batch controller 23. The batchcontroller 23 then compares the output of the converter 19, which isapplied on a line 28 by the comparator 20, with the high preset output21. If the total weight as indicated on the line 28 differs from thehigh preset output 21, an error weight and a new dribble weight estimateare determined for use in determining the high preset weight for thesame constituent for the next batch compounded for the same utilizingmeans. The total weight, as applied on the line 28, is also used as ascale tare for determining the high preset value for the nextconstituent to be fed.

The high preset output 21 of the batch controller 23 is individuallydetermined by the batch controller 23 for each constituent which issequentially fed into the batch receiving hopper 11. The high presetoutput 21 comprises the algebraic sum of the scale tare, a predeterminedformula quantity for the constituent to be fed, an estimated butunpredictable dribble quantity, and a compensation quantity for weighingerrors in the previous batch. The dribble quantity and the compensationquantity will usually have negative values. The estimated dribblequantity is determined for each constituent from the amount of theconstituent fed into the batch receiving hopper 11 after the switchingcircuits 26 stop the feed control means for such constituent. The lowpreset output 22 of the batch controller 23 is determined by subtractinga desired total slow feed constituent weight from the high preset output21. lt is preferable to determine a slow feed weight for each batchconstituent such that the slow feed time is the same for allconstituents.

After all the batch constituents are compounded in the batch receivinghopper 11, the batch controller 23 applies a signal on an output line29, causing the compounded batch to be delivered into a mixing hopper30. The compounded batch may be mixed in the mixing hopper 30 while thenext batch is being compounded in the batch receiving hopper 11. As soonas the compounded batch in the mixing hopper 30 is completely mixed, thebatch controller 23applies a signal on an output line 31 to causethe'mixed batch to be conveyed to a selected utilizing means. ln someinstances, the mixed compounded batch must be conveyed for a sufficientdistance that a first batch may be compounded in the batch receivinghopper 11 while a second batch is mixed in the mixing hopper 30 and athird batch is simultaneously being conveyed. A printer 32 mayoptionally be connected to the batch controller 23 for recording theactual quantities of the various constituents fed into the batchreceiving hopper 11 for each successive batch. Deviations in thequantities of each constituent fed into the batch receiving hopper 11,as well as other pertinent information, may also be recorded by theprinter 32.

Referring now to FIG. 2, the switching circuits 26 are shown in detail.The comparator 20 will apply one of three outputs to the switchingcircuits 26 on the output 24. When the output of the converter 19 isless than the low preset output 22 of the batch controller 23, thecomparator 20 will close a switch or relay 33. When the output of theconverter 19 lies between the low preset output 22 and the high presetoutput 21 of the batch controller 23, the comparator 20 will close aswitch or relay 34. Finally, when the output of the converter 19 isequal to or greater than the high preset output 21 of the batchcontroller 23, the comparator 20 will close a switch or relay 35.

The batch controller 23 similarly applies a number of signals on theoutput 25 for controlling the switching circuits 26. Feeding operationof the first constituent from the hopper 12, the second constituent fromthe hopper 14, or the third constituent from the hopper 16 is selectedby the batch controller by closing a first switch or relay 36, a secondswitch or relay 37, or a third switch or relay 38, respectively. Afterthe constituent is selected, the batch controller 23 will close a switchor relay 39 to initiate feeding of the selected constituent. The variousoutputs 24 and 25 from the comparator 20 and the batch controller 23 areconnected across a positive buss 40 and a negative buss 41 for operatinga number of control relays. A voltage is applied between the positivebuss 40 and the negative buss 41 by a suitable DC source 42.

The constituent feed control means 13, 15 and 17 are shown as pairs ofelectric motors operated from a suitable AC power source 43. The firstconstituent feed control means 13 includes a slow feed motor 44 and afast feed motor 45, the second constituent feed control means 15includes a slow feed motor 46 and a fast feed motor 47, and the feedcontrol means 17 for the third constituent 16 includes a slow feed motor48 and a fast feed motor 49, The slow feed motors 44, 46 and 48 and thefast feed motors 45, 47 and 49 may, for example, operate feed screws orfeed conveyors.

If the batch controller 23 selects, for example, the first constituentto be fed, the batch controller 23 closes the switch 36 to energize afirst constituent relay coil 50 from the power source 42. When the relaycoil 50 is energized, two associated pairs of normally open relaycontacts 50a and 50b are shorted. The relay contacts 50a and 50b areconnected in series between the first constituent slow feed motor 44 andthe first constituent fast feed motor 45, respectively, and the AC powersource 43. Since feeding is just being initiated, the output of theconverter 19 will be less than the low preset output 22 and thecomparator 20 will hold the switch 33 closed. The batch controller 23initiates the feeding operation by momentarily closing the switch 39 tomomentarily energize a relay coil 51. Relay contacts 51a and 51b, whichare associated with the relay coil 51, are momentarily shorted. Shortingthe relay contacts 51a energizes a relay coil 52, thereby shortingassociated pairs of contacts 52a and 52b. The relay contacts 520 areconnected in parallel with the relay contacts 51a and in se' ries withthe relay coil 52 to hold the relay coil 52 in an energized conditiononce energized by the contacts 51a. Similarly, since the switch 33 isclosed by the comparator 20, the momentary closure of contacts 5lb willenergize the relay coil 53 and associated relay contacts 53a, which arein parallel with the contacts 51b, hold the relay coil 53 in anenergized state.

The relay 53 also has associated normally open contacts 53b and normallyclosed contacts 53c for selectively applying power from the AC source 43to a fast feed buss 54 and a slow feed buss 55 to selectively actuatethe fast constituent feed motors 45, 47 and 49 or the slow constituentfeed motors 44, 46 and 48. Since the relays 52 and 53 are energized, therelay contacts 52b and 53b will be closed to apply voltage from thesource 43 to the fast feed buss 54. Also, since the batch controller 23has selected the first constituent by closing the switch 36, the relaycontacts 50b are shorted and the first constituent fast feed motor 45 isenergized.

The system will remain in the fast feed state until the comparatorindicates that the output of the converter 19 has reached the low presetoutput 22 by opening the switch 33 and closing the switch 34. When theswitch 33 is open, the relay coil 53 will become unenergized and theassociated contacts 5317 will open and the contacts 53c will close toapply voltage from the AC source 43 to the slow feed buss 55. The firstconstituent fast feed motor 45 will then become unenergized, and, sincethe relay contacts 50a are shorted, the first constituent slow feedmotor 44 will become energized from the slow feed buss 55. Since thecomparator 20 closed the switch 34, a relay coil 56 will becomeenergized to short a pair of associated contacts 56a, confirming to thebatch controller 23 that slow feed has been started.

Slow feed will continue until the output of the digital converter 19reaches the high preset output 21 of the batch controller 23, whereuponthe comparator 20 will open the switch 34 and simultaneously close theswitch 35. Closing the switch 35 will energize a relay coil 57 to open apair of normally closed contacts 57a which are in series with theenergized relay coil 52. The relay coil 52 will then be deenergized,opening the associated contacts 52b to remove the voltage from the slowfeed buss 55. The energized relay 57 also hasa pair of contacts57b whichare closed to indicate to the batch controller 23 that the firstconstituent feeding has been completed.

The switches and relay contacts which operate the relay coils 52, 53, 56and 57, are each protected from arcing by a series connected resistor 58and capacitor 59. After the feeding and weighing of the firstconstituent has been completed, the batch controller 23 will open theswitch 36 and will then select the second constituent by closing theswitch 37 to energize a relay coil 60. The relay coil 60 has anassociated pair of normally open contacts 600 which are connected inseries between the second constituent slow feed motor 46 and the slowfeed buss 55 and a pair of normally open contacts 60b which areconnected in series between the second constituent fast feed motor 47and the fast feed buss 54. Similarly, when the feeding and weighingoperation for the second constituent 14 is completed, the batchcontroller 23 will open the switch 37 and initiate feeding of the thirdconstituent by closing the switch 38 to energize a relay coil 61. Therelay coil 61 has associated pairs of normally open contacts 61a and 61bwhich are connected, respectively, between the slow feed buss 55 and thethird constituent slow feed motor 48 and the fast feed buss 54 and thethird constituent fast feed motor 49.

A resistor 62 is placed in series between the DC power source 42 and apower buss 63 for the constituent feed control relay coils S0, 60 and 61to prevent accidental feeding of more than one constituent at a time.When one of the coils 50, 60 and 61 is energized by the batch controller23 closing one of the switches 36, 37 and 38, respectively, the voltageappearing between the buss 63 and the buss 41 will be insufficient toenergize additional ones of the relay coils 50,60 and 61. However, thevoltage will still be sufficient to maintain the energized coil in anenergized state.

A normally closed overweight switch 64 is placed in series with the ACpower source 43 and the constituent feed motors 44-49. The normallyclosed overweight switch 64 is connected directly to the batch receivinghopper 11 to terminate the feeding of all constituents ifthe maximumhopper capacity should be exceeded.

What I claim is:

l. A method for the separate compounding of'individual batchescontaining predetermined measured quantities of various constituents,each of which batches is to be delivered to a selected utilizing means,said method comprising the steps of:

l. feeding a first constituent from a supply thereof into a batchreceiving hopper until the accumulated quantity thereof at least equalsa desired quantity plus any unpredictable overage resulting fromvariations in the feeding operation and constituent condition, saiddesired quantity comprising the algebraic sum of a. the predeterminedmeasured quantity for said first constituent and b. a first constituenterror quantity determined for the most recent batch delivered to theselected utilizing means;

2. weighing the total quantity of said first constituent accumulated insaid hopper including any overage;

. determining a new first constituent error quantity from said desiredquantity and the weighed quantity of said first constituent;

4. successively feeding additional constituents from supplies thereofinto said hopper until the accumulated quantity of each of saidadditional constituents at least equals a desired quantity for suchconstituent plus any unpredictable overage resulting from variations inthe feeding operation and constituent condition, said desired quantityfor each of said additional constituents comprising the algebraic sum ofa. the predetermined measured quantity for each of said additionalconstituents and b. an error quantity for each of said additionalconstituents and determined for the most recent batch delivered to theselected utilizing means;

. successively weighing the total quantities of each of said additionalconstituents accumulated in said hopper including any overage;

. successively determining a new error quantity for each of saidadditional constituents from said desired quantity for each of saidadditional constituents and the weighed quantity for the correspondingadditional constituent; and

7. delivering the compounded batch to the selected utilizing means.

2. A method for separate compounding of individual batches containingpredetermined measured quantities of various constituents, as defined inclaim 1, wherein the feeding of each of said first constituent and saidadditional constituents is at a fast rate when more than a predeterminedamount remains to be fed into said hopper and at a slow rate when lessthan the predetermined amount remains to be fed into said hopper.

3. A method for the separate compounding of individual batchescontaining predetermined measured quantities of various constituents, asdefined in claim 1, wherein the compounded batch is mixed prior todelivering to the selected utilizing means.

4. A method for the separate compounding of individual batchescontaining predetermined measured quantities of various constituents, asdefined in claim 3, wherein a batch is being compounded for a selectedutilizing means while a previously compounded batch for a selectedutilizing means is being mixed and a previously mixed compounded batchis simultaneously being delivered to a selected utilizing means.

5. A method for the separate compounding of individual batchescontaining predetermined measured weights of various constituents, eachof which batches is to be delivered to a selected utilizing means, saidmethod comprising the steps of:

l establishing the tare weight ofa batch receiving hopper;

2. feeding a first of such constituents from a supply thereof into saidhopper until the total weight of the accumulated first constituent andsaid hopper equals a desired weight, said desired weight comprising thealgebraic sum of a. the tare weight of said hopper,

LII

b. the predetermined measured weight for said first constituent,

c. an estimated unpredictable dribble weight for said first constituent,and

d. a first constituent error weight determined for the most recent batchcompounded for the selected utilizing means;

. determining a new first constituent dribble weight and a new firstconstituent error weight from said desired weight and the total weightof said hopper and the first constituent accumulated therein, includingany unpredictable dribble;

4. successively feeding the remainder of such constituents from suppliesthereof into said hopper until for each of such constituents the totalweight of said hopper and the constituents accumulated therein equals adesired weight, said desired weight for each of the remainder of suchconstituents comprising the algebraic sum of a. the tare weight of saidhopper,

b. the weight of all batch constituents previously accumulated in saidhopper,

c. the predetermined measured weight for the constituent being fed, 1

d. an estimated unpredictable dribble weight determined for theconstituent being fed, and

e. an error weight determined for the constituent being fed for the mostrecent batch compounded for the selected utilizing means;

5. determining new dribble and error weights for each of the remainderof such constituents from said desired weight for each constituent andthe total weight of said hopper and the constituents accumulatedtherein, including any unpredictable dribble, prior to feeding the nextone of the remainder ofsuch constituents; and

6. delivering the compounded batch to the selected utilizing means.

6. A method for the separate compounding of individual batchescontaining predetermined measured weights of various constituents, asdefined in claim 5, wherein the error weight for each one of theconstituents is equal to the difference between the desired weight forsaid one constituent and the total weight of said hopper, allconstituents accumulated in said hopper prior to feeding said oneconstituent and the amount of said one constituent actually accumulatedin said hopper.

7. A method for the separate compounding of individual batches of glasscontaining predetermined measured quantities of various glassconstituents, each of which batches is to be delivered to a selectedglass melting furnace, said method comprising the steps of:

l. feeding a first constituent from a supply thereof into a batchreceiving hopper until the accumulated quantity thereof at least equalsa desired quantity plus any unpredictable overage resulting fromvariations in the feeding operation and constituent condition, saiddesired quantity comprising the algebraic sum of a. the predeterminedmeasured quantity for said first constituent and b. a first constituenterror quantity determined for the most recent batch of glass deliveredto the selected glass melting furnace;

2. weighing the total quantity of said first constituent accumulated insaid hopper including any overage;

. determining a new first constituent error quantity from said desiredquantity and the weighed quantity of said first glass constituent;

4. successively feeding the remaining glass constituents from suppliesthereof into said hopper until the accumulated quantity of each of saidremaining glass constituents at least equals a desired quantity for suchconstituent plus any unpredictable overage resulting from variations inthe feeding operation and constituent condition, said desired quantityfor each of said additional constituents comprising the algebraic sum ofa. the predetermined measured quantity for each of said remaining glassconstituents and b. an error quantity for each of said remaining glassconstituents and determined for the most recent batch of glass deliveredto the selected glass melting furnace;

5. successively weighing the total quantities of each of said remainingglass constituents accumulated in said hopper including any overage;

6. successively determining a new error quantity for each of saidremaining glass constituents from said desired quantity for each of saidremaining glass constituents and the weighed quantity for thecorresponding remaining glass constituent; and

7. delivering the compounded batch to the selected glass meltingfurnace.

8. A method for the separate compounding of individual batches of glasscontaining predetermined measured quantities of various glassconstituents, as defined in claim 7, wherein the feeding of each of saidfirst constituent and said remaining glass constituents is at a fastrate when more than a predetermined amount remains to be fed into saidhopper and at a slow rate when less than the predetermined amountremains to be fed into said hopper.

9. A method for the separate compounding of individual batchescontaining predetermined measured weights of various constituents, eachof which batches is to be delivered to a selected utilizing means, saidmethod comprising the steps of:

l. establishing the tare weight of a batch receiving hopper;

2. successively feeding each of the constituents from supplies thereofinto said hopper until for each of the constituents the total weight ofsaid hopper and the constituents accumulated therein equals a desiredweight,

said desired weight for each one of the constituents comprising thealgebraic sum of Y a. the tare weight of said hopper,

b. the weight of all previously accumulated constituents in said hopper,

c. the predetermined measured weight for said one constituent,

d. an estimated unpredictable dribble weight determined for said oneconstituent, and

e. an error weight determined for said one constituent for the mostrecent batch compounded for the selected utilizing means;

. successively determining new dribble and error weights for eachconstituent from said desired weight for each constituent and the totalweight of said hopper and the constituents accumulated therein,including any unpredictable dribble, prior to feeding the next one ofthe constituents; and

4. delivering the compounded batch to the selected utilizing means.

10. A method for the separate compounding of individual batches of glasscontaining predetermined measured weights of various glass constituents,each of which batches is to be delivered to a selected glass meltingfurnace, said method comprising the steps of:

l. establishing the tare weight ofa batch receiving hopper;

2. feeding a first of such glass constituents from a supply thereofintosaid hopper until the total weight ofthe accumulated first glassconstituent and said hopper equals a desired weight, said desired weightcomprising the algebraic sum of a. the tare weight ofsaid hopper,

b. the predetermined measured weight for said first glass constituent,

c. an estimated unpredictable dribble weight for said first glassconstituent, and

d. a first constituent error weight determined for the most recent batchcompounded for the selected glass melting furnace;

3. determining a new first constituent dribble weight and a new firstconstituent error weight from said desired weight and the total weightof said hopper and the first constituent accumulated therein, includingany unpredictable dribble;

. successively feeding the remainder of such glass cond. an estimatedunpredictable dribble weight determined for the glass constituent beingfed, and

e. an error weight determined for the glass constituent being fed forthe most recent batch compounded for the selected glass melting furnace;

5. determining new dribble and error weights for each of the remainderof such glass constituents from said desired weight for each constituentand the total weight of said hopper and the constituents accumulatedtherein, including any unpredictable dribble, prior to feeding the nextone ofthe remainder ofsuch glass constituents; and

6. delivering the compounded batch to the selected glass meltingfurnace.

1. A method for the separate compounding of individual batchescontaining predetermined measured quantities of various constituents,each of which batches is to be delivered to a selected utilizing means,said method comprising the steps of:
 1. feeding a first constituent froma supply thereof into a batch receiving hopper until the accumulatedquantity thereof at least equals a desired quantity plus anyunpredictable overage resulting from variations in the feeding operationand constituent condition, said desired quantity comprising thealgebraic sum of a. the predetermined measured quantity for said firstconstituent and b. a first constituent error quantity determined for themost recent batch delivered to the selected utilizing means;
 2. weighingthe total quantity of said first constituent accumulated in said hopperincluding any overage;
 3. determining a new first constituent errorquantity from said desired quantity and the weighed quantity of saidfirst constituent;
 4. successively feeding additional constituents fromsupplies thereof into said hopper until the accumulated quantity of eachof said additional constituents at least equals a desired quantity forsuch constituent plus any unpredictable overage resulting fromvariations in the feeding operation and constituent condition, saiddesired quantity for each of said additional constituents comprisIng thealgebraic sum of a. the predetermined measured quantity for each of saidadditional constituents and b. an error quantity for each of saidadditional constituents and determined for the most recent batchdelivered to the selected utilizing means;
 5. successively weighing thetotal quantities of each of said additional constituents accumulated insaid hopper including any overage;
 6. successively determining a newerror quantity for each of said additional constituents from saiddesired quantity for each of said additional constituents and theweighed quantity for the corresponding additional constituent; and 7.delivering the compounded batch to the selected utilizing means. 2.weighing the total quantity of said first constituent accumulated insaid hopper including any overage;
 2. feeding a first of such glassconstituents from a supply thereof into said hopper until the totalweight of the accumulated first glass constituent and said hopper equalsa desired weight, said desired weight comprising the algebraic sum of a.the tare weight of said hopper, b. the predetermined measured weight forsaid first glass constituent, c. an estimated unpredictable dribbleweight for said first glass constituent, and d. a first constituenterror weight determined for the most recent batch compounded for theselected glass melting furnace;
 2. successively feeding each of theconstituents from supplies thereof into said hopper until for each ofthe constituents the total weight of said hopper and the constituentsaccumulated therein equals a desired weight, said desired weight foreach one of the constituents comprising the algebraic sum of a. the tareweight of said hopper, b. the weight of all previously accumulatedconstituents In said hopper, c. the predetermined measured weight forsaid one constituent, d. an estimated unpredictable dribble weightdetermined for said one constituent, and e. an error weight determinedfor said one constituent for the most recent batch compounded for theselected utilizing means;
 2. weighing the total quantity of said firstconstituent accumulated in said hopper including any overage;
 2. feedinga first of such constituents from a supply thereof into said hopperuntil the total weight of the accumulated first constituent and saidhopper equals a desired weight, said desired weight comprising thealgebraic sum of a. the tare weight of said hopper, b. the predeterminedmeasured weight for said first constituent, c. an estimatedunpredictable dribble weight for said first constituent, and d. a firstconstituent error weight determined for the most recent batch compoundedfor the selected utilizing means;
 2. A method for separate compoundingof individual batches containing predetermined measured quantities ofvarious constituents, as defined in claim 1, wherein the feeding of eachof said first constituent and said additional constituents is at a fastrate when more than a predetermined amount remains to be fed into saidhopper and at a slow rate when less than the predetermined amountremains to be fed into said hopper.
 3. A method for the separatecompounding of individual batches containing predetermined measuredquantities of various constituents, as defined in claim 1, wherein thecompounded batch is mixed prior to delivering to the selected utilizingmeans.
 3. determining a new first constituent dribble weight and a newfirst constituent error weight from said desired weight and the totalweight of said hopper and the first constituent accumulated therein,including any unpredictable dribble;
 3. determining a new firstconstituent error quantity from said desired quantity and the weighedquantity of said first glass constituent;
 3. successively determiningnew dribble and error weights for each constituent from said desiredweight for each constituent and the total weight of said hopper and theconstituents accumulated therein, including any unpredictable dribble,prior to feeding the next one of the constituents; and
 3. determining anew first constituent error quantity from said desired quantity and theweighed quantity of said first constituent;
 3. determining a new firstconstituent dribble weight and a new first constituent error weight fromsaid desired weight and the total weight of said hopper and the firstconstituent accumulated therein, including any unpredictable dribble; 4.successively feeding the remainder of such glass constituents fromsupplies thereof into said hopper until for each of such glassconstituents the total weight of said hopper and the constituentsaccumulated therein equals a desired weight, said desired weight foreach of the remainder of such glass constituents comprising thealgebraic sum of a. the tare weight of said hopper, b. the weight of allglass constituents previously accumulated in said hopper, c. thepredetermined measured weight for the glass constituent being fed, d. anestimated unpredictable dribble weight determined for the glassconstituent being fed, and e. an error weight determined for the glassconstituent being fed for the most recent batch compounded for theselected glass melting furnace;
 4. successively feeding additionalconstituents from supplies thereof into said hopper until theaccumulated quantity of each of said additional constituents at leastequals a desired quantity for such constituent plus any unpredictableoverage resulting from variations in the feeding operation andconstituent condition, said desired quantity for each of said additionalconstituents comprisIng the algebraic sum of a. the predeterminedmeasured quantity for each of said additional constituents and b. anerror quantity for each of said additional constituents and determinedfor the most recent batch delivered to the selected utilizing means; 4.delivering the compounded batch to the selected utilizing means. 4.successively feeding the remaining glass constituents from suppliesthereof into said hopper until the accumulated quantity of each of saidremaining glass constituents at least equals a desired quantity for suchconstituent plus any unpredictable overage resulting from variations inthe feeding operation and constituent condition, said desired quantityfor each of said additional constituents comprising the algebraic sum ofa. the predetermined measured quantity for each of said remaining glassconstituents and b. an error quantity for each of said remaining glassconstituents and determined for the most recent batch of glass deliveredto the selected glass melting furnace;
 4. A method for the separatecompounding of individual batches containing predetermined measuredquantities of various constituents, as defined in claim 3, wherein abatch is being compounded for a selected utilizing means while apreviously compounded batch for a selected utilizing means is beingmixed and a previously mixed compounded batch is simultaneously beingdelivered to a selected utilizing means.
 4. successively feeding theremainder of such constituents from supplies thereof into said hopperuntil for each of such constituents the total weight of said hopper andthe constituents accumulated therein equals a desired weight, saiddesired weight for each of the remainder of such constituents comprisingthe algebraic sum of a. the tare weight of said hopper, b. the weight ofall batch constituents previously accumulated in said hopper, c. thepredetermined measured weight for the constituent being fed, d. anestimated unpredictable dribble weight determined for the constituentbeing fed, and e. an error weight determined for the constituent beingfed for the most recent batch compounded for the selected utilizingmeans;
 5. determining new dribble and error weights for each of theremainder of such constituents from said desired weight for eachconstituent and the total weight of said hopper and the constituentsaccumulated therein, including any unpredictable dribble, prior tofeeding the next one of the remainder of such conStituents; and
 5. Amethod for the separate compounding of individual batches containingpredetermined measured weights of various constituents, each of whichbatches is to be delivered to a selected utilizing means, said methodcomprising the steps of:
 5. successively weighing the total quantitiesof each of said remaining glass constituents accumulated in said hopperincluding any overage;
 5. successively weighing the total quantities ofeach of said additional constituents accumulated in said hopperincluding any overage;
 5. determining new dribble and error weights foreach of the remainder of such glass constituents from said desiredweight for each constituent and the total weight of said hopper and theconstituents accumulated therein, including any unpredictable dribble,prior to feeding the next one of the remainder of such glassconstituents; and
 6. delivering the compounded batch to the selectedglass melting furnace.
 6. successively determining a new error quantityfor each of said additional constituents from said desired quantity foreach of said additional constituents and the weighed quantity for thecorresponding additional constituent; and
 6. successively determining anew error quantity for each of said remaining glass constituents fromsaid desired quantity for each of said remaining glass constituents andthe weighed quantity for the corresponding remaining glass constituent;and
 6. A method for the separate compounding of individual batchescontaining predetermined measured weights of various constituents, asdefined in claim 5, wherein the error weight for each one of theconstituents is equal to the difference between the desired weight forsaid one constituent and the total weight of said hopper, allconstituents accumulated in said hopper prior to feeding said oneconstituent and the amount of said one constituent actually accumulatedin said hopper.
 6. delivering the compounded batch to the selectedutilizing means.
 7. A method for the separate compounding of individualbatches of glass containing predetermined measured quantities of variousglass constituents, each of which batches is to be delivered to aselected glass melting furnace, said method comprising the steps of: 7.delivering the compounded batch to the selected utilizing means. 7.delivering the compounded batch to the selected glass melting furnace.8. A method for the separate compounding of individual batches of glasscontaining predetermined measured quantities of various glassconstituents, as defined in claim 7, wherein the feeding of each of saidfirst constituent and said remaining glass constituents is at a fastrate when more than a predetermined amount remains to be fed into saidhopper and at a slow rate when less than the predetermined amountremains to be fed into said hopper.
 9. A method for the separatecompounding of individual batches containing predetermined measuredweights of various constituents, each of which batches is to bedelivered to a selected utilizing means, said method comprising thesteps of:
 10. A method for the separate compounding of individualbatches of glass containing predetermined measured weights of variousglass constituents, each of which batches is to be delivered to aselected glass melting furnace, said method comprising the steps of: